"I've read the same things you have. Assuming the profile isn't wrong—and someone with her intelligence would be able to intentionally skew our profile, and hide her true feelings— assuming it isn't wrong, what conclusions are you drawing?"
"Zimmerman would only have left—and I don't care who might have facilitated it, because I doubt she would've—if it meant she could do work that, for one reason or another, she couldn ’t do here. She would never have left here just so she could reconstruct old information warfare viruses she's already designed for us. Doing old work would be pointless to her."
"What kind of work would she be doing?" D'Arcy asked. He leaned forward, his expression suddenly showing an intense interest in what Mecham was saying.
"Something that requires a Daedalus. Other than that, I don't know, and that's frightening." Mecham shook his head. "I suspect it has something to do with her work at MIT, since people from the Evolutionary Theorems Lab are working with her—but what it could be, I don't know. I'm not a mathematician, and, until now, I had thought that everything she did here was a logical extension of her work there."
D'Arcy nodded and leaned back. "True, perhaps, but nothing you've said means we change how we deal with this. Zimmerman is still a threat, probably more so than we ever thought. We still have to keep a tight watch on every Daedalus out there. Eventually the IUF will move on one of them, and then we have her."
"I just wish we hadn't lost Malcolm . . ."
Gideon and Ruth spent a good part of the evening on the subway. They went as far as Queens and back again, switching trains a number of times in an effort to foil any pursuit. Ruth was exhausted and spent most of the time asleep, leaning against Gideon's shoulder. Gideon was too keyed up to sleep. He spent most of the time staring at other passengers, wondering which ones were planning to attack them.
The rest of the time he thought about what was happening. Why was he here, next to Dr.
Zimmerman's sister, on the New York subway system?
"Julia, who are you?" he asked a mental image of the Doctor. "What are you doing?"
His only response was an enigmatic stare from those depthless gray eyes. What made her turn away? From her parents, from her sister, from her colleagues . . . ?
Christ, tell me why I turned away?
He must have been too tired, because that kind of question bore on things that he never wanted to think about.
Ruth must have felt him tense up because she sat up next to him and looked at him. "Are you all right?"
"I'm fine." The words were a whisper through clenched teeth.
"You're crying."
Gideon shook his head, but he raised his hand to his cheek and found wetness there. "It's just the smoke."
"It's all right," Ruth whispered. "You've been through a lot."
"It's not all right. It's never been all right." Gideon rubbed his forehead as if he could push the thoughts away, distract himself with what was going on around them now. "I'm a fraud," he whispered.
Ruth rubbed his shoulder.
"I couldn't hack it as a Fed," Gideon said. "I shouldn't be a cop either. I'll deserve it when IA pulls my badge."
"You aren't responsible—"
"My brother, my ex-partner . . . I got them both killed. Just because I wanted, someday, to be Rafe."
Ruth was silent for a long time before she said, "Rafe was your brother?"
Gideon nodded.
"I know what it is like to live in someone's shadow."
They were on the return trip from Jackson Heights, and morning light was streaming into the car as they rode over northern Queens. Ruth looked around as if she was looking for some reason to change the subject. "Where are we?" she finally asked.
"Queens," Gideon said, relieved to be talking about something else. "Going back to Manhattan."
She looked at the rest of the car. It was packed with people making the morning commute. Standing room only. She shook her head and whispered, "Is that safe?"
"I think we're all right now. The Israelis did us the favor of separating me from all the tracking devices—" Gideon felt the Micro-Uzi in his pocket. He'd had to strip off the silencer to allow it to fit.
"We should go to the FBI," Ruth whispered.
That was the easy answer, wasn't it? Gideon had been thinking the exact same thing for most of the night. There was one problem with it, though. "I can't."
"What do you mean, you can’t?"
"I can take you to them," Gideon said. "I can't stop."
Ruth's voice lowered even further. "Don't you realize that people are shooting at you?"
Gideon rubbed his healing leg and said, "I know." Not just at me. His voice was slow, halting, as he tried to explain why he needed to continue. Why he couldn't ask anyone for help. "I still have to find out
what's happening. Why." He closed his eyes and wondered how much of what he was saying was rationalization. "I can't back off now. I go to the Feds now, and the best that will happen is they'll hand me over to IA while they try and bury all their embarrassing mistakes." And I have to prove to myself that I can do this. Every time I've hit a snag, I've turned to someone to bail me out. Dad, Rafe, Kendal—
Ruth leaned back and sighed. Even with the motorcycle jacket, perhaps because of it, she looked very small and vulnerable. "You think I don't want to find Julie? She's my sister."
Gideon nodded. The train shot into a tunnel under the East River, briefly exchanging day for night. Gideon's hand drifted back toward the pocket with the gun. I'm doing this for Rafe. What he did for me has got to mean something.
Later on, as they rode under Manhattan, Gideon asked, "Do you think Julia could be working with the IUF?"
"Are you kidding? Why would she do that? It'd be pointless."
"She planned her disappearance," Gideon said. "Just like MIT. She even wiped her own home computer. Wherever she went, she planned to go there."
Ruth laughed. The sound was half derisive and half nervous. "You can't be suggesting that after all these years that Julie suddenly became political—not to mention political for these guys."
The train slowed for a stop, and the packed cars began to gradually empty out.
"What could they offer her?"
"To get her to jump ship at the NSA?" She shook her head. "You don't understand. All she really cares about is her work, it's almost a divine mission for her. From what I heard, the NSA gave her the best environment to conduct her work that she could possibly have."
Gideon thought back to their conversation in the restaurant. "Something she'd need a Daedalus for," he muttered.
"What?"
"What if they were watching us, had a man near us? What if something we did or said triggered the attack? What if we stumbled on something the IUF didn't want anyone to know?"
"Like what? We just talked about Julie's life, nothing secret—" Ruth shivered a little bit. "We didn't talk about anything worth shooting at us for."
Gideon stared out at a platform as the train pulled out. The lighted platform slid away and replaced itself with the depthless black of the tunnels. The clearest image was his own reflection in the window.
"She was working on something on her own. Something private. Everyone looking for Julia Zimmerman is afraid of what she was known to be working on for the NSA. What if the IUF offered her the opportunity to work on something she couldn't work on at the NSA?"
Ruth shook her head. "I know where you're going with that. I know it looks a lot like when she left MIT. But Julie isn't stupid. She'd consider the consequences of her actions. She knew that she could screw MIT, because she knew who would be backing her if things came to a head. She knew that she'd beat them." She turned her head and looked at Gideon. "This isn't the same. I can't see her making that decision. This is a no-win situation."
The train pulled to a stop again, and Gideon stood up. "Come on."
"What? Where are we going?"
"I want to make a stop at the library."
When Gideo
n sat behind one of the public terminals at the New York Public Library, Ruth asked him, "And what exactly do you expect to find here?"
Gideon cued up a search engine and said, "I want to look into what your sister might have been working
on."
"How the hell do you intend to do that?" Ruth pulled up a chair and sat next to him. "Are you some sort of police mathematician?"
"No," Gideon shook his head. "But I think the answer is somewhere in what we already know."
There was a pile of scratch paper and a small pencil box next to the computer. He took a sheet and a pencil and started scribbling a list of words;
"Information Warfare. Virus. Cryptography. Riemann. Number Theory. Aleph-Null. Evolutionary Algorithm. Zeta Function."
Gideon looked at the list of words. "That should be enough of a start."
Ruth watched as he scanned papers, articles, as well as the other detritus accumulated on the Internet. Those sites that weren't mathematical tended to be about private-sector information security. After about fifteen minutes, Gideon found a page that made him realize one of the fundamental reasons why the government was scared of losing Zimmerman. On the screen was a layman's description of public key cryptography, the de facto standard for secure personal communications on the Internet.
"No wonder they're frightened of her," Gideon whispered.
"What?" Ruth said.
"Look at this." Gideon tapped his finger on a paragraph that he had just scrolled onto the screen. "This whole process is based on very large prime numbers. . ."
"Okay, so?"
"That was at the heart of what she was doing at MIT, wasn't it?"
Ruth shrugged. "I never followed it very well. She was way past me by the time she left grade school."
Gideon scrolled through the article. "Most of the security on the Internet is based on these huge numbers, and on the fact that it's supposedly a practical impossibility to factor a four-thousand-bit number by brute force."
"So?"
"I'm not a mathematician, but one of the things that your sister's colleague, Dr. Nolan, told me—'Zimmerman was pushing the lab toward new theorems that could generate the primes, or factor huge numbers.'" Gideon shook his head. "No wonder the NSA wanted her, and wants her back. With that kind of algorithm there'd be no such thing as a secure communication on the Internet—or elsewhere for that matter. E-mail, credit-card transactions, private databases—you could crack any of it, all of it."
Ruth stared at the screen. "Do you think she managed that?"
"Why not?" Gideon said. "What would be worth more to an intelligence gathering agency? A factoring algorithm that renders the bulk of encrypted information in existence completely transparent." Gideon nodded to himself, leaning back. "And they have to be very careful bringing her back. If it became public knowledge that such an algorithm existed, it would become useless." Gideon tapped his fingers on the table. "That explains the government. . ."
Gideon was quiet a long while before Ruth interrupted him. "You don't sound completely sure."
Gideon shook his head. "I can make it fit with everything . . . except your sister. It fits with what the old man said about her designing parts of the NSA's computer security—" He sighed. "There's more to this. I know there's more to this. This doesn't explain why your sister disappeared. It certainly doesn't explain why she, or the IUF, would need a supercomputer."
"It doesn't? This sounds kind of heavy to me."
Gideon nodded. "But the work she was doing at MIT was using equipment anyone has access to, not particularly sophisticated. 200Mhz PCs. I could get more powerful computers used. So, if what she did was a direct outgrowth of the ET Lab, why would she suddenly need the kind of power a Daedalus provides? Not to mention, this is exactly the kind of thing the NSA was using her for. I'm sure that whatever she's doing now would have to be something that she couldn’t do at the NSA—"
"I keep telling you. She's not stupid. She wouldn't jump ship at the NSA unless she thought the odds were in favor of her getting away with it.
Gideon nodded. He'd been thinking along those lines himself. There was another possibility that Ruth wasn't seeing. What if Zimmerman didn't care about the odds? What if she was working on something that she thought was important enough to risk being hunted down by the Feds as a traitor?
There wasn't any question in Gideon's mind that Zimmerman had her own agenda. What if there was something she was working on in secret, ever since MIT? Maybe since before . . .
But what?
What could she think is that important?
Gideon stared at the screen, trying to think. Ruth looked at him and said, "Don't you think it's time to consider the FBI?"
Gideon looked at Ruth. "I doubt the government's priorities match ours— I don't think they care about bringing your sister in alive."
"And you do?"
The question made Gideon uncomfortable. He had been driven to this point by a need to discover what had happened in the warehouse, why Rafe had died. Somehow, his focus had changed. Julia Zimmerman had become his focus. He could rationalize it by saying that she had been the focus of what had happened at the warehouse. Was that the real reason? He was following this woman, finding himself fascinated by her history. . .
In his gut he knew that, if he discovered what she was doing, he could damage those who had shot him and killed Rafe. He knew he wanted to bring whatever happened to the press and to that Congressional hearing. He wanted to damage those who had damaged so much around him.
He wanted to vindicate himself.
But that wasn't it. Not completely.
He realized that he didn't want Julia Zimmerman to end like Rafe, or Kendal, or Davy Jones, or Kareem Rashad Williams. Whatever she had done, Gideon had an irrational belief that it wasn't treasonous. Somehow she was serving her first and only love. There was something in her that wasn't of Gideon's world. Gideon's world was constructed from self-serving politics, where his brother's death was some sort of bargaining chip, a political asset—or liability—depending on what side of the fence you were on.
Julia came from somewhere else. And, somehow, understanding her, what she was doing, would give Rafe's death the meaning that Gideon desperately needed. Gideon couldn't accept that all it had been was some interdepartmental screwup. . .
There was something larger, and much more important at stake.
Gideon looked at Ruth. Did he care about bringing Julia in alive? "I do," Gideon said quietly. "Believe me, I do."
Ruth looked at him a little oddly. "You don't have a crush on her, do you?"
Gideon laughed. "That's silly. I've never even met the woman."
He turned back to the computer screen and started calling up searches on the other terms that related to Dr. Zimmerman's work. As he worked, the phrase kept running through his head, I've never even met the woman.
He searched for things relating to "Evolutionary Algorithm," "Virus," and, "Information Warfare."
The search presented him with dozens of pages on the Evolutionary Algorithm. A few pages were actually archived copies of papers from the ET Lab at MIT. There were so many documents that Gideon threw Zimmerman's name into the search to pare down the list.
When he did that, he found all the MIT papers, and a document titled, "Tenth International Conference on Artificial Life."
Gideon stared at the title for a long time before he opened the document. He was remembering something Dr. Michael Nolan had said. "She began to act as if the programs we were creating were living creatures. . ." He also remembered the lone thing that she'd left on her own personal computer, a little icon labeled "life."
The document had an introduction to the term "artificial life." Gideon scanned the page, picking out phrases that caught his eye, or seemed important.
"Artificial Life labels human attempts to construct models—digital, biological, and robotic—that reproduce some of the essential properties of life. The goal of such models is to reveal the organizati
onal principles of living systems on Earth, and possibly elsewhere . . ."
". . . requires a truly interdisciplinary approach that knits together fields of knowledge as diverse as mathematics and biology, computer science and physics, engineering and philosophy . . ."
". . . an important part of this effort is a search for independent principles of living systems, which apply to any living system, regardless of biology—or lack thereof. Artificial Life also considers the possibilities of life, artificial alternatives to a carbon-based chemistry."
"This sounds like so much science fiction," Ruth said.
Gideon nodded. "But, according to Dr. Nolan, this kind of research has been going on for decades. He said some of the first Genetic Algorithms were produced on an Apple II computer."
Gideon checked the conference schedule and found Dr. Zimmerman's name.
"Sat. June 29: 8:30-9:15 Keynote Talk, Julia Zimmerman, The Biology of the Internet."
Gideon stared at the title of her talk for a long time. It was hard to reconcile with his idea of what Julia Zimmerman was involved in. So far he had pictured her as interested in obscure mathematical objects like the Zeta Function. The Internet seemed too "earthy" a topic for her.
He looked across at Ruth. "How interested is your sister in computers?"
"She's fascinated by them," Ruth said. "At least as far as they are a means to her ends. She once called them a mathematical telescope."
"Interesting metaphor."
"I think she meant that a computer can be used to see parts of the mathematical universe that would be otherwise undetectable."
There was an abstract of the speech available, and Gideon opened it.
"Has the term 'virus' stopped being metaphorical?" Gideon read. "With the increase in complexity of the
Internet, there has been an increase in the 'size' of the environment that can host uncontrolled entities. An average personal computer is packed with so much data that it is easy for foreign bits of code to hide undetected, and when it is connected to a network, the environment is vast. Security against computer viruses, because of their constant proliferation, has had to concentrate more and more on preventing the harmful effects of these viruses, and less on preventing the infection of the system. It is possible for a 'benign' virus, a virus that conducts no discernible attacks on its host, to propagate unimpeded. Evolution forces the eventual existence of such 'benign' viruses."
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